We present a 23 deg ^ { 2 } weak gravitational lensing survey of the Shapley supercluster core and its surroundings using gri VST images as part of the Shapley Supercluster Survey ( ShaSS ) .
This study reveals the overall matter distribution over a region containing 11 clusters at z { \sim } 0.048 that are all interconnected , as well as several ongoing cluster-cluster interactions .
Galaxy shapes have been measured by using the Kaiser-Squires-Broadhurst method for the g - and r -band images and background galaxies were selected via the gri colour-colour diagram .
This technique has allowed us to detect all of the clusters , either in the g -band or r -band images , although at different \sigma levels , indicating that the underlying dark matter distribution is tightly correlated with the number density of the member galaxies .
The deeper r -band images have traced the five interacting clusters in the supercluster core as a single coherent structure , confirmed the presence of a filament extending North from the core , and have revealed a background cluster at z { \sim } 0.17 .
We have measured the masses of the four richest clusters ( A3556 , A3558 , A3560 and A3562 ) in the two-dimensional shear pattern , assuming a spherical Navarro-Frenk-White ( NFW ) profile and obtaining a total mass of \mathcal { M } _ { ShaSS,WL } { = } 1.56 ^ { +0.81 } _ { -0.55 } { \times } 10 ^ { 15 } { M } _ { \odot } , which is consistent with dynamical and X-ray studies .
Our analysis provides further evidence of the ongoing dynamical evolution in the ShaSS region .